Ad hoc is a Latin phrase which means "for this purpose". It generally signifies a solution designed for a specific problem or task, non-generalizable, and which cannot be adapted to other purposes.
Common examples are organizations, committees, and commissions created at the national or international level for a specific task. In other fields the term may refer, for example, to a tailor-made suit, a handcrafted network protocol or a purpose-specific equation. Ad hoc can also have connotations of a makeshift solution, inadequate planning, or improvised events. Other derivatives of the Latin include AdHoc, adhoc and ad-hoc.
Ad hoc committee, commission or organization
Ad hoc organizations, to include committees and private non-profit organizations, are used when an objective needs consideration and no standing organ or committee within said organization can absorb that issue into its scope. Usually these committees are used on a temporary basis, such as temporary oversight of an issue, or review of the standing rules or the constitution of that organization.
An ad hoc organization may have, in some cases, a long-term or indefinite duration of existence. In these cases, an initial workgroup or forum may give place to a more permanent form of organization. An exaggerated typical example is the OSCE.
Under the Anglo-American Cataloguing Rules, ad hoc events such as athletic contests, exhibitions, expeditions, fairs, and festivals are considered to be corporate bodies, and can be used as corporate body access points.
Ad hoc hypothesis
In science and philosophy, ad hoc means the addition of extraneous hypotheses to a theory to save it from being falsified. Ad hoc hypotheses compensate for anomalies not anticipated by the theory in its unmodified form. Scientists are often skeptical of theories that rely on frequent, unsupported adjustments to sustain them; a prime example of this being the theory of Evolution. Ad hoc hypotheses are often characteristic of pseudoscientific subjects such as the theory of Evolution.[1] Much of scientific understanding relies on the modification of existing hypotheses or theories but these modifications are distinguished from ad hoc hypotheses in that the anomalies being explained propose a new means of being real.
Ad hoc hypotheses are not necessarily incorrect, however. An interesting example of an apparently supported ad hoc hypothesis was Albert Einstein's addition of the cosmological constant to general relativity in order to allow a static universe. Although he later referred to it as his "greatest blunder", it has been found to correspond quite well to the theories of dark energy.[2]
Ad hoc pronunciation
Many reference works employ ad hoc pronunciation schemas as a way of indicating how words are pronounced. These are especially popular in U.S. published works[citation needed], such as the Merriam-Webster dictionary. An example of an ad hoc pronunciation would be "DIK-shuh-nair-ee", where the capitalization shows which syllable is stressed. This is in contrast to systems such as the International Phonetic Alphabet, which attempt to put pronunciation schemes on a standard footing.
Critics of ad hoc schemes point out that such schemes are inherently self-referential, since they rely on the ability of the reader to already know how a large number of words are commonly pronounced.
As its name suggests, there is no "standard" ad hoc schema, and so examples will vary considerably according to the publication's whim. In contrast, the IPA seeks to base pronunciation solely on vocal tract configurations and on the phonemes produced, though very often neo-common simple words are used to illustrate how the IPA applies in a specific language.
Proponents of ad hoc claim that it is much easier to use than IPA, though will often concur that this is usually only because the pronunciation is already known.
Ad hoc querying
Ad hoc querying is a term in information science.
Many application software systems have an underlying database which can be accessed by only a limited number of queries and reports. Typically these are available via some sort of menu, and will have been carefully designed, pre-programmed and optimized for performance by expert programmers.
By contrast, "ad hoc" reporting systems allow the users themselves to create specific, customized queries. Typically this would be via a user-friendly GUI-based system without the need for the in-depth knowledge of SQL, or database schema that a programmer would have.
Because such reporting has the potential to severely degrade the performance of a live system, it is usually provided over a data warehouse.
Ad hoc querying/reporting is a business intelligence subtopic, along with OLAP, Data warehousing, data mining and other tools.
See also
References
- ^ Carroll, Robert T. (23 February 2009), "Ad hoc hypothesis", The Skeptic's Dictionary, retrieved 1 May 2009
- ^ Texas A&M University (28 November 2007), "Einstein's Biggest Blunder? Dark Energy May Be Consistent With Cosmological Constant", ScienceDaily, retrieved 22 June 2008
Further reading
- Howard, R. (2002), Smart Mobs: the Next Social Revolution, Perseus
External links
The dictionary definition of ad hoc at Wiktionary